LONDON - U.S. stock futures were little changed, after the Standard & Poor’s 500 Index slipped from its all-time high yesterday, as investors weighed the possibility that the Federal Reserve will scale back its stimulus program.

Carnival Corp. plunged 7 percent after the largest cruise operator lowered its profit projection for the second half of 2013. Urban Outfitters Inc. lost 2.8 percent as the retailer reported quarterly sales that missed analysts’ estimates. Home Depot Inc. rose 3.6 percent after raising its earnings forecast as the housing rebound boosts renovation spending.

S&P 500 futures expiring next month dropped less than 0.1 percent to 1,664.5 at 8:24 a.m. in New York. Contracts on the Dow Jones Industrial Average added 10 points, or 0.1 percent, to 15,329 today.

“I view a move by the Fed toward normalizing monetary policy as ultimately a good thing,” Liz Ann Sonders, chief investment strategist at Charles Schwab Corp., said on Bloomberg Television. Her firm has $2 trillion in client assets. “It will be a taper; they’re not going to grind this to a halt all of a sudden. If the reason is that economic growth has picked up with inflation expectations still fairly benign, then that’s the best reason for the Fed to do it.”

Fed Bank of St. Louis President James Bullard speaks on central-bank policy at the Institute for Monetary and Financial Stability at 5:30 p.m. in Frankfurt. Bullard said on April 17 that inflation had fallen too far below the Fed’s 2 percent target. He added that a further drop may prompt the central bank to increase its asset purchases.

Bernanke’s testimony

Fed Chairman Ben S. Bernanke testifies on the outlook for the U.S. economy before the Joint Economic Committee of Congress tomorrow. The Federal Open Market Committee also releases the minutes of its April 30-May 1 meeting tomorrow. Policy makers said after their last meeting that they will keep buying $85 billion of bonds every month, while standing ready to raise or lower purchases as conditions evolve.

Some Fed officials in recent months have signaled they favor scaling back the quantitative-easing program in the next few months. Stocks erased gains yesterday after Fed Bank of Chicago President Charles Evans said the U.S. economy has improved “quite a lot” as the central bank maintains record stimulus. The question now is “how much confidence we have that the improvements that have been made will continue and be sustained,” said Evans, who holds a vote on the FOMC this year.

The S&P 500 has surged 146 percent from its 12-year low in 2009, driven by better-than-estimated corporate earnings and three rounds of bond purchases from the Fed.

Eight companies on the S&P 500 post their financial results today. Of the stocks that have released earnings this season, 71 percent have beaten analysts’ estimates, while 52 percent have missed analysts’ sales predictions.

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